servos RC motor PWM

4. Example of Control Signal Results

8. Note: There are a handful of
other position sensors such as
encoders and resolvers, but the
variable resistor is common.

13. The blue area is an interesting part
of the servo

15. This is the feedback (closed) loop
that is always checking itself.

16. Where are servos used?
Remote-controlled or radio-controlled
toy cars, robots and airplanes,
industrial applications, robotics, in-
line manufacturing, pharmaceutics,
and food services

17. Advantages among different servo motors

High output power relative to motor size and weight.

Closed loop system-It gives itself feedback as to its position
or speed

High efficiency. It can approach 90% at light loads.

High torque to inertia ratio. It can rapidly accelerate loads.

Has "reserve" power. 2-3 times continuous power for short
periods.

Has "reserve" torque. 5-10 times rated torque for short
periods.

Audibly quiet at high speeds.

Resonance and vibration free operation.

18. Disadvantages among different servo motors

Requires "tuning" to stabilize feedback loop.

Motor "runs away" when something breaks. Safety circuits
are required.

Peak torque is limited to a 1% duty cycle.

Motor can be damaged by sustained overload.

Bewildering choice of motors, encoders, and servodrives.

Motor develops peak power at higher speeds. Gearing
often required.

RC Servo motors have a limitation of movement unless
hacked.

Usually cost more than a stepper motor